1. Field of the Invention
The present invention generally relates to a friction clutch with automatic compensation for wear inside the pressure plate, which pressure plate can preferably be fastened to the flywheel of an internal combustion engine, the friction clutch comprising the pressure plate located in a torsionally stationary and axially movable manner in the clutch housing, a membrane spring located between the clutch housing and pressure plate, which membrane spring is braced against the clutch housing and the pressure plate, and which membrane spring applies pressure to the pressure plate thereby moving the pressure plate towards the flywheel, a clutch disc with friction linings between the pressure plate and the flywheel, and an adjustment device to increase the distance between the membrane spring and the pressure plate as a function of the wear on the friction lining, the adjustment device being in the form of a ring element which ring element is guided on a guide diameter of the pressure plate concentric to the axis of rotation of the friction clutch.
2. Background Information
Such a friction clutch is disclosed, for example, by German Patent Specification 29 20 932, which corresponds to U.S. Pat. No. 4,207,972 granted to Zeidler on Jun. 17, 1980. On this type of friction clutch, the components of the mechanism which automatically compensates for wear consists of a ring element which is guided on a guide diameter of the pressure plate concentric to the axis of rotation, and which ring element is in contact by means of oblique or slanted circumferential surfaces with corresponding opposite oblique surfaces of the pressure plate. By means of a tension spring, force is applied to the circumference of the ring element opposite the pressure plate, so that the ring element, as a result of the torsion relative to the pressure plate, can increase the distance from the pressure plate. A membrane spring is in contact on the side of the ring element opposite the pressure plate. When wear occurs on the friction lining of the clutch disc, and when the membrane spring lifts up from the ring element, the latter is twisted by the tension spring into the gap which is formed, and thus there is a compensation for wear. The membrane spring therefore remains constant over the entire wear distance in its position relative to the clutch housing, so that the forces exerted by the membrane spring also remain constant. The model of the prior art is quite complex and expensive, since a precise machining of the pressure plate is necessary, and a complicated ring element must by used.